I agree with Speeral. I really don't want to see ability trees. I hate to say it but if I wanted to put points in trees, I'd play WoW. With any ability tree everyone will just pick the most powerful choices.

I think the only flaw with the current class system is that the abilities are linked to weapons.

I think if the classes wern't linked to weapons it would allow them to be more diverse. I dont think we should lose the ability to change class any time we like, but I do think it should be done in a different way.

I would love to see something like menu where you can change your active class, any time you want.

Then you could give the classes more diversity in the weapons they use. Ideally I would like to see each class get a choice between a few different weapons. Like Gladiator for example could use a sword, axe, polearm and each of these weapons could grant access to gladiator only abilities.

You could go one step further and add high end class restricted weapons too.

I'm not saying every class should be able to use every weapon, but having a choice between 2 or 3 options would be really nice.